Linux 5.12 compat: idmapped mounts

In Linux 5.12, the filesystem API was modified to support ipmapped
mounts by adding a "struct user_namespace *" parameter to a number
functions and VFS handlers. This change adds the needed autoconf
macros to detect the new interfaces and updates the code appropriately.
This change does not add support for idmapped mounts, instead it
preserves the existing behavior by passing the initial user namespace
where needed.  A subsequent commit will be required to add support
for idmapped mounted.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Co-authored-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Coleman Kane <ckane@colemankane.org>
Closes #11712
This commit is contained in:
Coleman Kane
2021-03-20 00:00:59 -04:00
committed by GitHub
parent 330c6c0523
commit e2a8296131
22 changed files with 557 additions and 123 deletions
+65
View File
@@ -0,0 +1,65 @@
dnl #
dnl # Supported mkdir() interfaces checked newest to oldest.
dnl #
AC_DEFUN([ZFS_AC_KERNEL_SRC_MKDIR], [
dnl #
dnl # 5.12 API change
dnl # The struct user_namespace arg was added as the first argument to
dnl # mkdir()
dnl #
ZFS_LINUX_TEST_SRC([mkdir_user_namespace], [
#include <linux/fs.h>
int mkdir(struct user_namespace *userns,
struct inode *inode, struct dentry *dentry,
umode_t umode) { return 0; }
static const struct inode_operations
iops __attribute__ ((unused)) = {
.mkdir = mkdir,
};
],[])
dnl #
dnl # 3.3 API change
dnl # The VFS .create, .mkdir and .mknod callbacks were updated to take a
dnl # umode_t type rather than an int. The expectation is that any backport
dnl # would also change all three prototypes. However, if it turns out that
dnl # some distribution doesn't backport the whole thing this could be
dnl # broken apart into three separate checks.
dnl #
ZFS_LINUX_TEST_SRC([inode_operations_mkdir], [
#include <linux/fs.h>
int mkdir(struct inode *inode, struct dentry *dentry,
umode_t umode) { return 0; }
static const struct inode_operations
iops __attribute__ ((unused)) = {
.mkdir = mkdir,
};
],[])
])
AC_DEFUN([ZFS_AC_KERNEL_MKDIR], [
dnl #
dnl # 5.12 API change
dnl # The struct user_namespace arg was added as the first argument to
dnl # mkdir() of the iops structure.
dnl #
AC_MSG_CHECKING([whether iops->mkdir() takes struct user_namespace*])
ZFS_LINUX_TEST_RESULT([mkdir_user_namespace], [
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_IOPS_MKDIR_USERNS, 1,
[iops->mkdir() takes struct user_namespace*])
],[
AC_MSG_CHECKING([whether iops->mkdir() takes umode_t])
ZFS_LINUX_TEST_RESULT([inode_operations_mkdir], [
AC_MSG_RESULT(yes)
AC_DEFINE(HAVE_MKDIR_UMODE_T, 1,
[iops->mkdir() takes umode_t])
],[
ZFS_LINUX_TEST_ERROR([mkdir()])
])
])
])